Question with adding a subwoofer
 

I haven't really looked yet, but i'm going to be adding the subs from my old car into the BRZ and I was wonder if since there is going to be a dealer installed subwoofer accessory is there already wiring to the trunk that could be used to add an aftermarket sub?

I was wondering the same thing, but haven't dug in there yet to find out if the wiring already exists.

Well, the audio amplifier looks to be in the trunk. I'll confirm this in about 1.5 weeks. The stock FR-S CD player has subwoofer outputs, but I didn't see an extra harness installed for it.

If I were to guess, the car was not wired for a rear subwoofer. That seems like a lot of extra for a dealer installed item. But again, I could be wrong. The first week in July I plan to start my subwoofer install, which means the car will be stripped down for wiring and just plain curiosity.

Even if the car were wired for a subwoofer, the chances of it working with your equipment from the other car is very low. OEM wiring works with OEM subs and amps, not aftermarket.

Well regardless of the connector there should be at least a i'm assuming line level audio in the factory wiring (if it exists) which means there's no reason with a little cutting and soldering that I couldn't use those wires for the audio signal to the amp, the power wiring that would exist however wouldn't be adequate and I would have to at least run a cable to the battery for power. But really i'm just trying to figure where to tap the audio signal off, I could tap it off the rear speakers, but given their small size I wouldn't be surprised if they don't have a high pass filter from the amp already and thus wouldn't be good to use for the subs.

The stock head unit seems to have some RCA outputs. I'd use those long before I did speaker level inputs. I've seen them in some pictures people have posted. You might be able to hook on to the remote turn on from the rear amp though. I'd still run new power for the amp though.

Ooh, the stock head unit has RCA outputs? that's even more awesome, now I wish I pulled the RCA cable out of my Magnum before I traded it in, at the time it just didn't seem worth the effort.

Yeah, new power cable is a must since I doubt the factory wiring would be 8GA (if it exists) for the dealer installed sub, though if there are RCA jacks in the head unit that means the dealer installed sub probably using those and they run the RCA cables for them, which makes me think that if they have to run those they wouldn't have put the power wires in. It's a shame the BRZ doesn't have the battery in the trunk, that makes wiring the amp a breeze, loved that in my Magnum.

The FR-S does, has it been confirmed for the BRZ?

Agreed on all points. I was in a hurry earlier so didn't have time to post all the info, but you're on the right track. Sounds like you know more than the average person.

I'm assuming you're using aftermarket stuff? The FR-S has RCA outputs like the other guys have said. On other vehicles, you can tap the audio signal right at the head unit and put your LOC right in the dash.

Yeah, I know quite a bit about car audio, in my last car I replaced the entire stereo system and ran all new wires for everything and even had a custom dock built into the dash to mount an Android tablet, and ultimately i'll be doing the same in the BRZ, mainly just waiting for the head unit I want to come out, but I need to at least get the subs in for now to make the stereo at least bearable.

Yup, I have the entire aftermarket system I pulled out of my last car before I traded it in. I'll have to pop open the dash this weekend to verify if the BRZ head unit also has RCA outs like the FR-S, I'm going to go with likely yes cause they are probably using it for their subwoofer accessory and I can't see them not having different connection methods for the FR-S and BRZ.

The BRZ unit doesn't. Only the FR-S does.

That sucks then. I'll sell you my FRS Headunit cheap lol. Its coming out this weekend or next.

While looking around today I noticed under the trunk liner up near the drivers side rear seat there a metal box with cables in it, I wonder if that could be the factory amp, I hadn't pulled apart the trim panels though to see if the wires went to the speakers or not, does anyone know if that is the amp?

That would be it.

The oem brz subs are going to be on the driver side of the trunk

I thought I saw an extra wire coming from the battery terminal but I didn't really think to look where it went to (or what gauge it was). Then again, my FR-S came with the Bespoke "Premium" audio package.

BRZ Head Unit Pinouts are in Impreza Forum
 

The BRZ head unit is the same as the one in the 2012 Impreza. So, this thread about upgrading the Impreza audio may have some info of use to you:
http://forums.nasioc.com/forums/show....php?t=2298834

Ill be watching this thread with interest. I have some ED 6" subs that have been sitting in my garage unused for years. I would like to use those in the FR-S.

Can anyone explain or provide a wiring diagram for the factory amp?

Im also trying to figure out where to tap into the system with a line out converter.

It would make sense to tap it there since it would save time,
avoid removing the center console & head unit,
and keep all my audio electronics tucked away in the trunk.

I have a Limited BRZ. Ended up running everything from the head unit and power cable from the battery. The rear amplifier in the trunk is used to power the back speakers. You could tap off of that, but for me, it was easier to do it off the back of the head unit. Take a look at my Public Profile, navigate to my web page, and look at the pix.

How did you run the power cable? Did you drill the firewall or did you use an existing opening? I am assuming that you ran the remote-on using a pin off the HU??? Thanks.

I ran the power cable on the passenger side through the stock grommet to the passenger foot well from the engine compartment behind the battery.

Here is the head unit pin outs:

10-pin power/speaker harness
1 2 - - 3 4
5 6 7 8 9 10
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 RF+ (SUBWOOFER)
2 LF+
3 +12V Accessory (AMPLIFIER)
4 +12V Battery/Constant
5 RF- (SUBWOOFER)
6 LF-
7 Ground
8 Power Antenna (provides power to Subaru's antenna booster amp)
9 [NC] {amp remote turn-on signal on Toyota HUs, not Subaru}
10 Illumination+


6-pin power/speaker harness
1 - - 2
3 4 5 6
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 RR+
2 LR+
3 RR-
4 [NC]
5 Dimmer (Illumination-)
6 LR-


28-pin SWC/aux/mic harness
1 .. 14
15 .. 28
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 [NC]
2 Reverse Gear
3 Illumination Dimmer Cancel (Bright mode)
4 Mic ? (separate, possibly ground)
5 Mic ? (twisted w/ 19)
6 Ground (not connected to mic)
7-14 [NC]
15 [NC]
16 [NC]
17 VSS
18 [NC]
19 Mic ? (twisted w/ 5)
20 [NC]
21 SWC Audio (Seek, Volume)
22 SWC Mode + Phone
23 SWC Common
24 [NC]
25 Aux enable
26 Aux audio Right
27 Aux audio shield/ground
28 Aux audio Left


16-pin rear camera socket
1 ... 8
9 ... 16
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
4 ?
5 ?
6 Parking brake (CUT AND PUT RADIO SIDE ON GROUND TO 28 PIN HARNESS GROUND)
7 Camera +6V supply (HU sends power to OEM Camera)
8 Camera Video In
15 Camera Detect (connect this to chassis ground)
16 Shield/ground

Just curious, what effect does cutting the parking brake wire and grounding it actually do?

Is that more for the GPS?

It bypasses the safeguards put in place so that as you drive, you can stream/watch movies via usb, etc.

I am going to try to use the stock amp location in the trunk and replace it with a 4 channel amp. I'd like to use those subwoofer outputs for the signal instead of using the front L/R signal that is already there in the trunk.

I took a look at the amp in the trunk and I don't think the power going to that amp is going to cut it. It was a very thin gauge wire and just run off a 15A fuse, so I think I'd be blowing that fuse even with my 200W amp. The good news is the L/R signal coming from the radio is there, and the wiring to the front door speakers is there, so I should be able to tap into that to wire in a 4 channel amp.

wiring diagram
http://i.imgur.com/imde0.png

location of amp (power connector is on the right)
http://i.imgur.com/3q3Hhl.jpg

closeup of signal connnector
http://i.imgur.com/k06dll.jpg

The wires going into this connector are:
(1 is at the bottom left of the connector in the photo, 10 is the top right)
1 - Pink (looks orange?) - Left speaker +
2 - Blue - Right speaker +
3 - Light Green - Left signal +
4 - White - Right signal +
5 - Violet - Left speaker -
6 - Red - Right speaker -
8 - Green - remote signal
9 - Yellow - Left Signal -
10 - Sky Blue - Right signal -

spaceywilly, Thank you - this is very helpful. Do they use any bandwidth filters on the signals going to the woofer or tweeters?

To verify that that amp is used to power the front door speakers I got in the car and turned on the radio with that amp unplugged. Only the dash and rear speakers were going and there was definitely no bass going to those speakers, so it sounds like they are using high pass at least on those speakers. I am going to use another high pass for the front door speakers once I add the sub, and a low pass on the sub. I'm not sure if they are sending the full signal to the door speakers or cutting out the highs, but just from listening it sounds like they are getting the full signal.

Spaceywilly, one additional question. If you are going to install a bigger amp should you take the r/l signal before it gets to the oem amp or do you have to connect it to the r/l speaker leads after oem amplification?

I'm hoping to use the signals before the oem amp and remove that amp entirely. If those signals don't work with my amp I'll use the speaker level signals.

Let me know. Thanks.

Did you finish this project? If so, do you have any pictures of the setup / finished product? I plan on adding a subwoofer this weekend using this method. Last night I ran the power cable from the engine bay to the rear, and I hope to finish this weekend.

Not yet, I'm waiting to run the power cable as you did. I think instead of removing the front speaker amp as I mentioned in that post I'm just going to add the subwoofer using a 2ch amp that I had. The downside of this is that I can't cut the low frequencies out of the front door speakers, so I might have to get a 4ch amp at some point, but I think just adding the sub will make a huge difference. So this way, I will just use the left channel + and - signals and the remote signal from that connector.

Here is my current setup. It took me about 1.5 hrs on Thursday evening to route the power cable through the firewall and car. On Friday afternoon, I took about 1 hr and 45 mins to finish the rest of the setup. However I am not done yet, I rushed it because I had dinner plans and a soccer game later that evening. I would work on it now, but it's too damn hot in Houston,TX right now. My next step is to clean it up and make it look pretty.
The current setup is;
-760 watts max Sony xploid amp
-10" Infinity sub dual voice coil, (4 or 2 ohm, I forgot) - 500 watt rms / 1000 max
-ported sub enclosure
-low pass filter

I am using the left / right speaker signal and remote on signal coming into the factory amp.

My future plans are similar to spacewilly's idea. Get a space and power efficient 4 CH Amp, a smaller subwoofer and enclosure, run the door speaker off 2 ch's, and the sub from 2 ch bridged into one.

My current sub and enclosure is too damn loud, it rattles the whole car and the bass is too much.. lol. I didn't know it was going to be like this, I have the amp about 1/4 way turned on the gain, and the bass bumps super hard... anyways it'll do for now.

INFINITY 10" SUB + SONY AMP

Attachment 10390

Attachment 10391

LOW PASS FILTER

Attachment 10392

CABLE RAN UNDERNEATH REAR PASSENGER SEAT

Attachment 10393

CABLE RAN THROUGH FIREWALL FRONT PASSENGER FOOTWELL

Attachment 10394

CABLE RAN THROUGH FIREWALL - EXISTING GROMMET FOUND REAR LEFT OF BATTERY

Attachment 10395

This is the plugs on the back of the Head Unit correct. Wanna make sure its that and not the amp in the back you are talking about. Either way thanks I was tryn to find the amp remote turn on!

These plugs are the ones found behind the Head Unit.

sweeeT ill throw a meter on there today to confirm the toyota amp turn on!


Verified today that is the amp turn on for toyota or umm scion I mean.

Spaceywilly,

Do you know what fuse is linked to that amp in the trunk? Thanks.

Jeff

I will take a look later, looking at the wiring diagrams it looks like a 15A fuse labelled (possibly) ANP in the Instrument panel J/B assembly. I think it's in the bottom right of the fuse box inside the car.

If you are going to add a sub.. just use the RCA outs. No point in giving up sound quality and running a line out converter or tapping into those little front door speaker wires, when even the stock base model HU gives you sub RCA outputs.

That being said, finding a harness for a facroty sub could make running a remote amp wire a little easier.

That's only the case for the FR-S HU, not the BRZ's.

I still wonder how they are going to be hooking up the OEM sub that's listed in the BRZ's accessories catalog without the RCA outs.